January 9, 2009

Sheep Farm Husbandry - NZ Breeding history, Flock recording, Group breeding

Sheep, husbandry, breeding, breed structure, NZ flock recording, cooperation among breeders, group breeding schemes

By Dr Clive Dalton

Traditional breed structure
When new breeds were established in their countries of origin, usually from merging other breeds, breeders formed breed societies and breed associations to share their livestock and common interests. These breeders had the best animals and they became the source of genes for commercial farmers.

So traditionally a triangular structure developed, with the stud breeders in the apex and the commercial farmers who bought their stock (mainly rams) in the base. Breeders in the middle were multipliers who bought the top genes, multiplied them to eventually sell to the commercial farmers, and make a profit on the way. The multipliers gained status by having the top genes even if they did not breed them.

Gene flow
The flow of genes was always one way down from apex to base, and reverse flow was not allowed. This was because the animals – no matter how good they were in the commercial flocks in the base, were not allowed to be “registered” in the breed associations’ “stud books”. So commercial farmers could not breed rams or ewes for sale because of concern about lack of proof of “breed purity”. The traditional dogma said that only registered sheep had good genes, and any others had no guarantee of this.

The theory said that by registering sheep in a studbook, breeders kept control of the quality of the stock that were then used to improve the rest of the population – i.e. the commercial flocks in the country. This theory was certainly sound in the days of Thomas Bakewell – the “Great Improver” in the mid 1700s, as he did produce the best animals that improved and revolutionised British livestock farming.

So this system went around the globe, and Britain became the “stud farm of the world” where breeders were urged to go back and renew the “pure” genes that were inevitably lost in their own countries. In New Zealand the practice died in sheep quicker than in cattle, for even as late as 1970 breeders were still going to Perth to buy Aberdeen Angus bulls at enormous cost, bred in a stud of half a dozen cows. It was a wonderful marketing job by the UK stud breeders.

This system may have served the needs of New Zealand breeders into the early 1900s, but became an enormous brake on progress when you tried to apply the principles of population genetics. These came in when statistics and maths were applied to animal breeding by animal geneticists like J.L Lush and C.E. Terrill in America and by A.L Rae in New Zealand in the 1940s and 1950s.

Flock recording in NZ
With Rae’s stimulation, a sheep breeding revolution started in New Zealand in the late 1960s and early 1970s. It started with the setting up of the National Flock Recording Scheme (NFRS) in 1967 (again with Rae’s leadership), to offer a recording service to stud breeders or any others interested who wanted to record performance data like lambing percentage, live weights and fleece weights. Up to that time only pedigrees were officially recorded with all other emphasis on physical traits required by the breed organisation. In the front of each flock book was a long and detailed description of what the ideal animal should look like of that particular breed.

Coopworth & Perendale
The development of the Coopworth at Lincoln College, and the Perendale at Massey University in the 1950s and their rapid expansion were also great drivers of the NFRS. Indeed the Coopworth Society made it mandatory for all stud breeders to be on the NFRS, and they stimulated massive progress in the attitudes of other breeds.

The revolution came mainly from commercial sheep breeders who found innovative ways to tag lambs, and record large numbers of sheep in their own commercial flocks to identify top sheep, and to have their data processed by the NFRS. They were all desperate to speed up flock improvement, and this often started by catching and tagging two-tooth ewes that produced twins. Both the ewe and her ewe lambs were tagged as future replacements.

Rams from unregistered flocks
As these farmers kept on recording, they started to keep rams from their “elite” ewes and were amazed at the quality of the rams produced. They did not deny that these identified top sheep had got their genes from their traditional stud breeders – and were more than a bit aggrieved that they could not register them by the breed society or association. There were many heated discussions over this, as the only way you could get non-registered sheep into the stud book at that time was by grading up which could take 10-12 years if things went according to plan.

These breeders then got up enough courage to actually use their own rams – and of course didn’t need to buy rams as many from their traditional stud ram supplier. So the ram buyer missed out on income, the breed society missed out on registration fees, and the stock and station companies missed out on their commission from arranging sales. Political pressure was even brought to bear to stop this state of affairs and certainly curb the activities of certain government scientists (including the author) who were seen to be encouraging these developments. These were stimulating times for animal geneticists and I invented a new branch of genetics – “political genetics”!

Rams for sale
Things got worse (or better depending on your viewpoint) when these commercial breeders became ram sellers. They sold rams to fellow sheep farmers who wanted sheep that had been selected on performance, in the rugged commercial conditions where their offspring were to live and perform, and not in small studs on land that should have been running dairy cows.

In the large commercial flocks, intense selection pressure was being applied to ram selection because there were so many animals to choose from. It really was survival of the fittest, and was in total contrast to the traditional small stud flocks of often under 100 ewes, where a very high proportion of rams born were saved by assisting their dams to lamb, and which were sold as stud sires often passing on these traits.

This drive to select sheep from larger populations was also driven by the massive move to “easy-care” lambing to reduce costs by farmers who were weary of pulling lambs out of wool-blind ewes. They found that the stud breeders were not changing their objectives fast enough to keep up with the commercial realities of the time.

Group breeding schemes
Then finding high-performance sheep in commercial flocks triggered another part of the revolution – the setting up of Group Breeding Schemes by some innovative farmers again guided by A.L Rae of Massey University. Some of the farmers were Rae’s former students and at one time there were at least a dozen active group breeding schemes operating.

Here commercial breeders identified their top ewes (usually two-tooths) on their own farms and contributed them to a central flock usually on a group member’s farm for ease of recording. Rams bred in the nucleus then went back to be used on contributors’ farms at a ratio of 1 ram for 4 contributed two-tooths. If you wanted any more rams you paid for them. The nucleus-flock farmer was paid a management fee by the contributors for the extra work in recording.

This shook the stud industry to the core, and some of the small stud breeders went out of business. But others could see the benefits of more intense selection for economic traits to improve genetic gain that commercial farmers were screaming for to survive the very tight economic conditions of the 1970s and 1980s. The stud industry emerged from the British empire’s Victorian past and in the mid 1980s saw the need for change – especially when farm subsidies disappeared overnight in 1984.

Breed societies today are vastly changed organisations. As well as offering full registration services for sheep, they also handle the performance recording needs of breeders and offer advice on all aspects of sheep breeding. They all eventually joined the revolution started by forward-looking commercial sheep farmers led by Prof. Al Rae at Massey and Prof. Ian Coop at Lincoln.

WARNING: History is a dangerous business and is littered with examples of bias and conjecture, because it’s inevitably one person’s view. Like most things on this website (especially the bits written by me!) comments are the author’s view based on my active involvement in the revolution.

This material is provided in good faith for information purposes only, and the author does not accept any liability to any person for actions taken as a result of the information or advice (or the use of such information or advice) provided in these pages.

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